Methods of forming doped and un-doped strained semiconductor materials and semiconductor films by gas-cluster-ion-beam irradiation and materials and film products

Abstract

Methods and apparatus are described for irradiating one or more substrate surfaces with accelerated gas clusters including strain-inducing atoms for blanket and / or localized introduction of such atoms into semiconductor substrates, with additional, optional introduction of dopant atoms and / or C. Processes for forming semiconductor films infused into and / or deposited onto the surfaces of semiconductor and / or dielectric substrates are also described. Such films may be doped and / or strained as well.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of priority to U.S. Provisional Application Ser. Nos. 60 / 544,516 filed 14 Feb. 2004, and 60 / 621,911 filed 25 Oct. 2004, each entitled “Formation of Doped and Un-Doped Strained Silicon and Semiconductor Films by Gas-Cluster Ion Irradiation”, and both of which are hereby incorporated by reference in their entirety.FIELD OF THE INVENTION[0002]This invention relates generally to the formation of locally strained regions in semiconductor substrates and doped or un-doped thin films of semiconductor materials on semiconductor or other substrates, and more particularly, through energetic gas-cluster ion irradiation.BACKGROUND OF THE INVENTION[0003]The characteristics of semiconductor materials such as, for example, silicon, germanium and gallium arsenide and other semiconductors have been exploited to form a large variety of useful devices in the fields of electronics, communications, electro-optics, and nano-t...

AI Technical Summary

Benefits of technology

"The present invention provides a method for introducing germanium or other strain-inducing atoms into semiconductor substrates by using energetic cluster ion irradiation. This method can be used to form semiconductor films or strained semiconductor films on the surfaces of semiconductor or dielectric substrates. Additionally, the invention allows for the simultaneous introduction of germanium or other strain-inducing atoms and dopant atoms into semiconductor substrates. The technical effects of this invention include improved semiconductor device performance and the formation of high-quality semiconductor films."

Problems solved by technology

Previous methods (such as epitaxy) for producing blanket strained-silicon on semiconductor or insulating (typically silicon oxide) substrates involve low throughput, high temperature, techniques that result in undesirably high costs per wafer.

Such local-strain techniques have also been expensive to implement and typically utilize high processing temperatures that can be a disadvantage in some applications.

Conventional ion implantation using atomic or molecular ions of materials containing germanium has not proven an efficient way of introducing germanium into silicon for creating strain.

The required high concentrations of at least a few atomic percent of germanium in silicon for effective strain production require such high conventional ion implantation doses so as to be economically impractical with conventional ion implantation equipment.

In general, the solid solubility limit of the dopant in silicon has been an upper limit for effective doping.

Consequently, the impact effects of large clusters are substantial, but are limited to a very shallow surface region.

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